Food-caching western scrub-jays keep track of who was watching when   总被引：1，自引：0，他引：1  

Dally JM  Emery NJ  Clayton NS 《Science (New York, N.Y.)》2006,312(5780):1662-1665

Western scrub-jays (Aphelocoma californica) hide food caches for future consumption, steal others' caches, and engage in tactics to minimize the chance that their own caches will be stolen. We show that scrub-jays remember which individual watched them during particular caching events and alter their recaching behavior accordingly. We found no evidence to suggest that a storer's use of cache protection tactics is cued by the observer's behavior.  相似文献   

Severity and persistence of footrot in Merino sheep experimentally infected with a protease thermostable strain of Dichelobacter nodosus at five sites     

LJ DEPIAZZI  WD ROBERTS  CD HAWKINS  MA PALMER  DR PITMAN  NC MCQUADE  PD JELINEK  DJ DEVEREAUX  RJ RIPPON 《Australian veterinary journal》1998,76(1):32-38

Objective To test the hypothesis that ovine footrot associated with a thermostable protease strain of Dichelobacter nodosus undergoes self cure or is sustained as an annually recurring disease, depending on the environment.
Design and procedure Forty Merino sheep from a single blood line were infected with a protease thermostable strain of D nodosus a t each of five sites in Western Australia. Footrot lesions and microscopic evidence of D nodosus were recorded every fortnight for 2.5 years, supplemented by laboratory culture. Rainfall, soil and air temperature, pasture quantity and composition and soil types were also recorded. Flocks that apparently self cured were relocated to a more favourable site for footrot in the final spring season.
Results The maximum prevalence of feet with clinical footrot lesions was 80.6, 1.3, 14.4, 3.8 and 88.1% at the five sites. Severe footrot occurred for three consecutive spring seasons at one site that had clay loam soil and at least 3500 kg/ha total pasture dry matter annually. However, the infection was asymptomatic for up to 10 weeks between outbreaks. D nodosus was isolated from flocks for 2.5 years at only two sites, although there was microscopic evidence of the organism at other sites in the final year. A thermolabile variant (strain U6) of D nodosus was isolated from the two sites where footrot persisted.
Conclusion Depending on time and location, ovine footrot induced by a protease thermostable strain of D nodosus either self cured or persisted as annual outbreaks interspersed with periods of asymptomatic infection.  相似文献   

Cross-protective immunity to canine adenovirus type 2 by canine adenovirus type 1 vaccination.     

J B Emery  J A House  W R Brown 《American journal of veterinary research》1978,39(11):1778-1783

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The Importance of Interactions Among Nutrition, Seasonality and Socio-sexual Factors in the Development of Hormone-free Methods for Controlling Fertility     

RJ Scaramuzzi  GB Martin 《Reproduction in domestic animals》2008,43(S2):129-136

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Generation of immunity against Fusobacterium necrophorum in mice inoculated with extracts containing leucocidin     

D L Emery  J A Vaughan 《Veterinary microbiology》1986,12(3):255-268

The capacity of extracts from toxigenic and non-toxigenic ruminant strains of Fusobacterium necrophorum to protect against challenge with homologous and heterologous bacteria was examined in mice. The numbers of F. necrophorum which were infective or lethal for mice increased 5- to 8-fold in animals which had been previously inoculated with complete Freund's adjuvant (FCA). Although preparations containing lipopolysaccharide (LPS) and outer membrane proteins (OMP) from several strains gave protection against a non-toxigenic strain (FnB-3), they did not significantly immunize mice against a challenge infection with a toxigenic bovine strain, FnB-1. Only material which had been prepared by gel filtration of 18-h liquid culture supernates of toxigenic F. necrophorum elicited significant immunity against homologous challenge with FnB-1. This preparation contained LPS and the majority of the leucotoxic activity. However, passive protection was not afforded to mice inoculated with bovine or rabbit sera which possessed high neutralization titres against the leucocidin.  相似文献   

Fertilisation and weed control effects on yield and weeds in durum wheat grown under rain-fed conditions in a Mediterranean climate     

A GARCÍA-MARTÍN  RJ LÓPEZ-BELLIDO†  & JM COLETO 《Weed Research》2007,47(2):140-148

Summary A field study was undertaken to examine the effect of fertiliser type and weed control system on grain yield, yield components and weed population in durum wheat ( Triticum turgidum. var. durum) grown in a 4-year rotation [bare fallow–barley ( Hordeum vulgare )–vetch ( Vicia sativa )–wheat]. Fertilisation treatments were: no fertilisation, organic fertilisation with 2500 kg ha⁻¹ of compost (sheep manure and cereal straw) and chemical fertilisation with 100–60–60 kg ha⁻¹ of NPK. Weed-control treatments were: no control, herbicide, harrowing with long-flex spring tines and strip sowing with inter-row hoeing. Chemical fertilisation increased grain yield with respect to the other treatments, amongst which no significant differences were noted. Weed-control systems afforded no improvement in yield compared with controls; indeed, yields obtained using inter-row hoeing were lower. The weed population consisted of a large variety of species, of which the most important were Convolvulus arvensis and Polygonum aviculare . Application of weed-control systems reduced weed density. Herbicide was the most effective, reducing weed biomass by 80%, whilst harrowing and hoeing reduced weed biomass by 40% and 52% respectively. Inter-row hoeing does not appear to be a viable alternative to herbicides, when used as the sole weed control method in a non-diverse cropping system in Mediterranean climates. The lack of response to compost suggests a need for further long-term research.  相似文献   

Assessment of the potential toxicity of a poison for rabbits, pindone (2-pivalyl 1, 3 indandione), to domestic animals     

GR MARTIN  RJ SUTHERLAND†  ID ROBERTSON†  WE KIRKPATRICK  DR KING  PJ HOOD† 《Australian veterinary journal》1991,68(7):241-243

The toxicity of pindone, a rabbit poison, to horses, cattle, goats, chickens, dogs and cats was investigated, using extension of prothrombin time (PT) as an index of poisoning. The daily dose of pindone, administered for 5 days, ranged from 0.3 mg/kg for dogs to 2.5 mg/kg for chickens. This range of dose rates was considered to be indicative of the worst possible case that could arise following a campaign of baiting for rabbits. Although significant elevations in PT (more than double baseline values) were noted in all species other than horses, clinical signs of anticoagulant poisoning were not observed in any of the species tested. From the observed PT, cattle and cats appeared to be the most susceptible, and horses the least susceptible, to pindone toxicity. The half-lives of the elevated PT were calculated as 3.1 days for cattle, 2.8 days for goats and chickens, 1.9 days for horses and dogs and less than one day for cats. It is proposed that these half-lives can be used as a guide for determining the duration of treatment of pindone-affected animals.  相似文献   

Isolation of Mycobacterium avium subsp paratuberculosis from the semen of rams with clinical Johne''s disease     

J EPPLESTON  RJ WHITTINGTON 《Australian veterinary journal》2001,79(11):776-777

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Detection of Clostridium botulinum types C and D toxin by ELISA   总被引：3，自引：0，他引：3  

RJ THOMAS 《Australian veterinary journal》1991,68(3):111-113

An ELISA to detect Clostridium botulinum type D toxin was developed using polyclonal antibodies to a semi-purified toxic complex of the neurotoxin. Sensitivity of the ELISA for detecting type C and type D toxin compared with mouse inoculation was 70% and specificity 96% on samples from animals with botulism diagnosed on clinical signs and herd history. However, both mouse inoculation and the ELISA failed to detect toxin in many animals with a presumptive diagnosis of botulism. Some cross-reaction was seen with Clostridium novyi type A, but not with other clostridial species. While the ELISA described here cannot replace mouse inoculation for the diagnosis of botulism, it is a useful additional test.  相似文献   

A tissue-culture, modified live-virus rabies vaccine for dogs: report on development and clinical trial     

J B Emery  A Y Elliott  D E Bordt  G R Burch  E E Kugel 《Journal of the American Veterinary Medical Association》1968,152(5):476-482

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